Elevated Plasma Levels of LDL Cholesterol Promote Dissecting Thoracic Aortic Aneurysms in Angiotensin II-Induced Mice

Calcitriol Supplementation Protects Against Apoptosis and Alleviates the Severity of Abdominal Aortic Aneurysm Induced by Angiotensin II and Anti-TGFβ

The present study aims to assess the effect of vitamin D deficiency (VDD) and its supplementation on the severity of AAA in mice. AAA was induced by AngII and anti-TGF-β administration. Animals were divided into four groups: Sham, mice with AAA, mice with AAA, and VDD, and mice with AAA supplemented with calcitriol. Blood pressure, echocardiography, abdominal aortic tissues, and plasma samples were monitored for all groups. VDD was associated with enhanced activity of cleaved MMP-9 and elastin degradation and positively correlated with the severity of AAA. Calcitriol supplementation decreased the INFγ/IL-10 ratio and enhanced the Nrf2 pathway. Moreover, Cu/Zn-superoxide dismutase expression and catalase and neutral sphingomyelinase activity were exacerbated in AAA and VDD groups. Furthermore, calcitriol supplementation showed a significantly lower protein expression of caspase-8, caspase-3, Bid, and t-Bid, and prevented the apoptosis of VSMCs treated by AngII and anti-TGF-β. Calcitriol supplementation may alleviate AAA severity and could be of great interest in the clinical management of AAA. VDD enhances antioxidant enzymes activity and expression, whereas calcitriol supplementation alleviates AAA severity by re-activating Nrf2 and inhibiting apoptotic pathways.

Role of thyroid hormone in an experimental model of atherosclerosis: the potential mediating role of immune response and autophagy

Accumulating evidence has revealed that several conditions related to abnormal thyroid hormone status, such as dyslipidemia, hypertension, or hypercoagulable state, can exacerbate atherosclerotic vascular disease. Thyroid hormone effects on vascular smooth muscle cells and endothelial cells have also been studied extensively. However, only limited information is available on thyroid hormone-mediated immune response in current review articles on the pathophysiology of atherosclerosis. This report thus presents an overview of the recent advances in the understanding of the dynamic interactions taking place between thyroid hormone status and immune response in the pathogenesis of atherosclerosis. In particular, we focus on macrophages and T-lymphocytes, which have been recognized as important determinants for the initiation and development of atherosclerosis. Numerous studies have revealed the role of autophagy in immune cells produced in atherosclerosis. In addition, thyroid hormones induce autophagy in several cells and tissues, such as liver, skeletal muscles, lungs, and brown adipose tissue. Our research group, among others, have reported different targets of thyroid hormone-mediated autophagy, including lipid droplets (lipophagy), mitochondria (mitophagy), and aggregated proteins (aggrephagy). Based on these findings, thyroid hormone-mediated autophagy could serve as a novel therapeutic approach for atherosclerosis. We also consider the limitations of the current murine models for studies on atherosclerosis, especially in relation to low-density lipoprotein-cholesterol driven atherosclerotic plaque.

Single-Cell RNA Sequencing Reveals Smooth Muscle Cells Heterogeneity in Experimental Aortic Dissection

Purpose: This study aims to illustrate the cellular landscape in the aorta of experimental aortic dissection (AD) and elaborate on the smooth muscle cells (SMCs) heterogeneity and functions among various cell types.

Methods: Male Apolipoprotein deficient (ApoE−/−) mice at 28 weeks of age were infused with Ang II (2,500 ng/kg/min) to induce AD. Aortas from euthanized mice were harvested after 7 days for 10×Genomics single-cell RNA sequencing (scRNA-seq), followed by the identification of cell types and differentially expressed genes (DEGs). Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was conducted.

Results: AD was successfully induced in ApoE−/− mice. scRNA-seq identified 15 cell clusters and nine cell types, including non-immune cells (endothelials, fibroblasts, and SMCs) and immune cells (B cells, natural killer T cell, macrophages, dendritic cells, neutrophils, and mast cells). The relative numbers of SMCs were remarkably changed, and seven core DEGs (ACTA2,IL6,CTGF,BGN,ITGA8,THBS1, and CDH5) were identified in SMCs. Moreover, we found SMCs can differentiate into 8 different subtypes through single-cell trajectory analysis.

Conclusion: scRNA-seq technology can successfully identify unique cell composition in experimental AD. To our knowledge, this is the first study that provided the complete cellular landscape in AD tissues from mice, seven core DEGs and eight subtypes of SMCs were identified, and the SMCs have evolution from matrix type to inflammatory type.

Risk Factors Affecting Cognitive Impairment of the Elderly Aged 65 and Over: A Cross-Sectional Study

Objectives

Elderly population with cognitive impairment has been accelerating in China. This study aimed to explore the relationship between each risk factor and each cognitive domain to provide evidence for risk prevention of controlling impaired cognitive function in elderly.

Methods

This cross-sectional study analyzed the cognitive status of the elderly aged 65 and above in three communities in Shizhong District of Jinan City. Cognitive status was assessed by MMSE. The influencing factors of cognitive impairment were analyzed by chi square test, correlation analysis and regression analysis.

Results

Among 1,171 participants, 643 were defined as cognitive impairment with an incidence of 54.9%. And we found that there were significant differences in the incidence of cognitive impairment among residents with different gender, age, education level, hypertension and LDL-C (P < 0.05). However, BMI, marital status, smoking, physical exercise, T2DM, TC, TG and HDL-C had no significant differences in the incidence of cognitive impairment. In addition, education level (b = 1.194, P <0.001), age (b = −0.040, P = 0.001), LDL-C (b = 0.169, P = 0.018) had statistical significance on the total score of MMSE according to binary logistic regression analysis.

Conclusion

Gender, age, education level, hypertension and LDL-C had significant differences in the incidence of cognitive impairment. And these risk factors could provide a basis for the early screening and intervention of cognitive impairment in the elderly.

Research progress on the pathogenesis of aortic dissection

Aortic dissection (AD) is a critical cardiovascular disease due to the separation of media and adventitia caused by the rupture of vascular wall intima. The disease has a high mortality rate of about 1% to 3% for each additional hour, since the adventitia of the aorta can rupture and bleed to death at any time. Although great progress has been made in clinical treatment of aortic dissection, and the mortality rate has been significantly reduced, the pathogenesis is still not very clear. At present, related studies have confirmed that inflammation of aortic wall promotes the occurrence and development of AD. Although the mechanism of aortic dissection is more complicated, some studies have shown that the infiltration of monocytes/macrophages into the aortic wall is the main pathogenic mechanism of the disease. This review introduces the latest research results on the mechanism of macrophage infiltration and plasticity in aortic dissection.

Genome-Wide Identification of Associations of Circulating Molecules With Spontaneous Coronary Artery Dissection and Aortic Aneurysm and Dissection

Circulating proteins play functional roles in various biological processes and disease pathogenesis. The aim of this study was to highlight circulating proteins associated with aortic aneurysm and dissection (AAD) and spontaneous coronary artery dissection (SCAD). We examined the associations of circulating molecule levels with SCAD by integrating data from a genome-wide association study (GWAS) of CanSCAD and 7 pQTL studies. Mendelian randomization (MR) analysis was applied to examine the associations between circulating molecule levels and AAD by using data from UK Biobank GWAS and pQTL studies. The SCAD-associated SNPs in 1q21.2 were strongly associated with circulating levels of extracellular matrix protein 1 (ECM1) and 25 other proteins (encoded by CTSS, CAT, CNDP1, KNG1, SLAMF7, TIE1, CXCL1, MBL2, ESD, CXCL16, CCL14, KCNE5, CST7, PSME1, GPC3, MAP2K4, SPOCK3, LRPPRC, CLEC4M, NOG, C1QTNF9, CX3CL1, SCP2D1, SERPINF2, and FN1). These proteins were enriched in biological processes such as regulation of peptidase activity and regulation of cellular protein metabolic processes. Proteins (FGF6, FGF9, HGF, BCL2L1, and VEGFA) involved in the Ras signaling pathway were identified to be related to AAD. In addition, SCAD- and AAD-associated SNPs were associated with cytokine and lipid levels. MR analysis showed that circulating ECM1, SPOCK3 and IL1b levels were associated with AAD. Circulating levels of low-density lipoprotein cholesterol and small very-low-density lipoprotein particles were strongly associated with AAD. The present study found associations between circulating proteins and lipids and SCAD and AAD. Circulating ECM1 and low-density lipoprotein cholesterol may play a role in the pathology of SCAD and AAD.

Macrophage-biomimetic anti-inflammatory liposomes for homing and treating of aortic dissection

Aortic dissection (AD) is a life-threatening disease featured by the dissection of intimal layer and the formation of a blood-filled false lumen within the aortic wall. Recent studies revealed that the formation and progression of AD lesions is closely related to vascular inflammation and macrophage infiltration. However, the potential efficacy of anti-inflammatory therapy on the prevention and treatment of AD has not been extensively investigated. Herein, we proposed a biomimetic anti-inflammatory liposome (PM/TN-CCLP) co-loaded with curcumin and celecoxib (CC), modified with cell-penetrating TAT-NBD fusion peptide (TN), and further camouflaged by isolated macrophage plasma membrane (PM), as a potential nanotherapy for AD. In vitro results showed that PM/TN-CCLP exhibited low cytotoxicity and elevated cellular uptake by inflammatory macrophages, and prominently inhibited the transendothelial migration, inflammatory responses and ROS generation of macrophages. Moreover, the PM/TN-CCLP treatment significantly prevented the H₂O₂-induced smooth muscle cell apoptosis. In vivo experiments were performed on the acute and chronic AD mouse models, respectively. The results verified the elevated accumulation of PM-camouflaged liposome at the aorta lesions. Further, the anti-inflammatory liposomes, especially PM/TN-CCLP, could reduce the rupture rate of dissection, prevent the loss of elastic fibers, and reduce MMP-9 expression as well as macrophage infiltration in the aortic lesions. Notably, as compared with free drugs and TN-CCLP, the PM/TN-CCLP treatment displayed the longest survival period along with the minimal aortic injury on both acute and chronic AD mice. Taken together, the present study suggested that the macrophage-biomimetic anti-inflammatory nanotherapy would be a promising strategy for the prevention and therapy of aortic dissection.

Association of NFE2L2 Gene Polymorphisms with Risk and Clinical Characteristics of Acute Type A Aortic Dissection in Han Chinese Population

The present study is aimed at investigating the association of NFE2L2 gene polymorphisms with risk and clinical characteristics of acute type A aortic dissection (AAAD) in a Han Chinese population. Six SNPs (rs1806649, rs13001694, rs2364723, rs35652124, rs6721961, and rs2706110) in NFE2L2 were genotyped using SNaPshot Multiplex Kit in 94 adult patients diagnosed with AAAD at our hospital, and 208 healthy Han Chinese subjects from the 1000 Genomes Project were served as the control group. The CC genotype of rs2364723 (CC versus (GC+GG), OR = 2.069, 95% CI: 1.222-3.502, p = 0.006) and CC genotype of rs35652124 (CC versus (CT+TT), OR = 1.889, 95% CI: 1.112-3.210, p = 0.018) were identified as risk factors for AAAD. Multivariable linear regression analysis revealed that the CC genotype of rs2364723 (β = 5.031, 95% CI: 1.878-8.183, p = 0.002) and CC genotype of rs35652124 (β = 4.751, 95% CI: 1.544-7.958, p = 0.004) were associated with increased maximum ascending aorta diameter of AAAD. Patients carrying rs2364723 CC genotype had a higher incidence of coronary artery involvement (31% vs. 12%, p = 0.027), while patients carrying rs35652124 CC genotype had a higher incidence of brain ischemia (9% vs. 0%, p = 0.045). In conclusion, NFE2L2 gene polymorphisms were correlated with risk and severity of AAAD in Han Chinese population.

Senescence and senolytics in cardiovascular disease: Promise and potential pitfalls

Ageing is the biggest risk factor for impaired cardiovascular health, with cardiovascular disease being the cause of death in 40 % of individuals over 65 years old. Ageing is associated with an increased prevalence of atherosclerosis, coronary artery stenosis and subsequent myocardial infarction, thoracic aortic aneurysm, valvular heart disease and heart failure. An accumulation of senescence and increased inflammation, caused by the senescence-associated secretory phenotype, have been implicated in the aetiology and progression of these age-associated diseases. Recently it has been demonstrated that compounds targeting components of anti-apoptotic pathways expressed by senescent cells can preferentially induce senescence cells to apoptosis and have been termed senolytics. In this review, we discuss the evidence demonstrating that senescence contributes to cardiovascular disease, with a particular focus on studies that indicate the promise of senotherapy. Based on these data we suggest novel indications for senolytics as a treatment of cardiovascular diseases which have yet to be studied in the context of senotherapy. Finally, while the potential benefits are encouraging, several complications may result from senolytic treatment. We, therefore, consider these challenges in the context of the cardiovascular system.

Association of Toll-Like Receptor 4 Gene Polymorphisms with Acute Aortic Dissection in a Chinese Han Population

Background

Inflammation may be involved in the pathogenesis of acute aortic dissection (AAD). Toll-like receptor 4 (TLR4) is known to play a critical role in regulating the immune and inflammatory processes. To date, the relationship between genetic variation of TLR4 and AAD is far from clear. The purpose of our study was to illustrate the relevance of TLR4 polymorphisms with the susceptibility to AAD.

Methods

A total of 222 AAD patients and 222 controls were enrolled in this study. Frequency distributions of TLR4 polymorphisms (rs10759932 in the promoter and rs11536889 in the 3′-untranslated region) were determined by the KASP method. Clinical parameters were acquired from subjects' medical records, and serum TLR4 levels were collected from our previously published data.

Results

We found that rs10759932 polymorphism was associated with a reduced risk of AAD in the overall population (CC vs. TT: OR = 0.393, 95%CI = 0.164‐0.939, P = 0.036; recessive model: OR = 0.439, 95%CI = 0.196‐0.984, P = 0.045) and subgroup analyses stratified by sex. The GC genotype and dominant model of rs11536889 conferred a significantly higher risk of AAD compared with GG genotype in female subjects (GC vs. GG: OR = 3.382, 95%CI = 1.051‐10.885, P = 0.041; dominant model: OR = 3.043, 95%CI = 1.041‐8.900, P = 0.042). In addition, a significant interaction between the rs11536889 recessive model and dyslipidemia was observed for an increased risk of AAD (P_interaction = 0.038, OR = 15.229) after the adjustment for potential clinical covariates. We also used the false-positive report probability (FPRP) analysis to validate the significant results. Furthermore, rs11536889 polymorphism could affect the maximal aortic diameters of AAD (P = 0.037), while AAD patients carrying CC genotype of rs10759932 showed lower serum TLR4 levels than TT genotype carriers (P = 0.043).

Conclusions

Our findings provide evidence for the association between TLR4 polymorphisms and AAD susceptibility in a Chinese Han population, which may have some implications for understanding the role of TLR4 in the pathophysiology of AAD.

The Role of Macrophages in Aortic Dissection

Aortic dissection (AD) is a fatal disease that accounts for a large proportion of aortic-related deaths and has an incidence of about 3–4 per 100,000 individuals every year. Recent studies have found that inflammation plays an important role in the development of AD, and that macrophages are the hub of inflammation in the aortic wall. Aortic samples from AD patients reveal a large amount of macrophage infiltration. The sites of macrophage infiltration and activity vary throughout the different stages of AD, with involvement even in the tissue repair phase of AD. Angiotensin II has been shown to be an important factor in the stimulation of macrophage activity. Stimulated macrophages can secrete metalloproteinases, inflammatory factors and other substances to cause matrix destruction, smooth muscle cell apoptosis, neovascularization and more, all of which destroy the aortic wall structure. At the same time, there are a number of factors that regulate macrophages to reduce the formation of AD and induce the repair of torn aortic tissues. The aim of this review is to take a close look at the roles of macrophages throughout the course of AD disease.

Elevated serum TC and LDL-C levels in Alzheimer's disease and mild cognitive impairment: A meta-analysis study

Serum lipid levels such as triglyceride and cholesterol has been reported to play an important role in the pathophysiological process of Alzheimer disease (AD) and mild cognitive impairment (MCI). However, it still remains controversial in different studies. Here, we performed a meta-analysis to assess the importance of serum levels of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) in AD and MCI patients. PubMed, China National Knowledge Infrastructure (CNKI) system database were used to identify 17 studies (10 AD-only + 4 MCI-only + 3 shared AD/MCI), including 2333 cases and 3615 healthy controls (HC). We found that compared with HC, both the serum TC levels [SMD = 0.58; 95%CI (0.25, 0.90); P = 0.001) and the serum LDL-C levels [SMD = 0.7780; 95%CI (0.3940, 1.1521); P = 0.000] were higher in cognitive impairment population (including AD and MCI) than those in HC, respectively. Furthermore, we analyzed the serum TC and LDL-C levels in AD and MCI patients. We found that the serum TC levels [SMD = 0.76; 95% CI (0.13, 1.40); P = 0.019]1 and the LDL-C levels [SMD = 1.40; 95% CI (0.70, 2.10; P = 0.000] were increased in AD patients. In the MCI patients, the serum TC levels [SMD = 0.30; 95%CI (0.01, 0.59); P = 0.041] had a significantly upward trend, while the LDL-C levels had no significant change, compared with HC subjects. However, there is no significant changes in HDL-C and TG levels in AD or MCI patients. Therefore, our results suggested that the elevated TC and LDL-C levels may be a potential risk factor for cognitive impairment.

The Role of Animal Models in Elucidating the Etiology and Pathology of Abdominal Aortic Aneurysms: Development of a Novel Rupture Mechanism Model

Existing animal models do not replicate all aspects of abdominal aortic aneurysms (AAAs), including the rupture mechanisms. From histopathological analyses conducted in humans, it has been found that the vasa vasorum of the AAA wall is the starting point of circulatory failure and that bulging and dilatation of the abdominal aorta occurs through inflammation and tissue degeneration. We created a new animal model (the hypoperfusion-induced model) of AAAs. In this study, we describe the current animal models of AAAs and present the utility of our new model of AAAs.